From WHMCS Documentation
[edit] Modifying the Logo
The logo displayed on the PDF invoices is located in the images folder. To change this to your own logo simply upload your logo to the images folder and name it "logo.jpg".
[edit] Editing Text & Content
You can fully customize the PDF invoices such as adding or removing text, altering the layout or adding furthur images & formatting. This is done by editing the template file invoicepdf.tpl in your active template folder. The file contains all the code relating to the layout and display of the invoice in its PDF format. You will need a basic working knowledge of PHP coding in order to understand and modify the file.
The PDF's are generated using TCPDF & you can find a list of variables here: http://www.fpdf.org/
[edit] Available Variables
The following variables are available for usage in the pdfconfig.php file.
- $datecreated - The date the invoice was created
- $duedate - The date the invoice is due
- $datepaid - Shows paid date/time if invoice is set to Paid
- $userid - Client ID Number
- $clientsdetails["firstname"] - Client Info First Name
- $clientsdetails["lastname"] - Client Info Last Name
- $clientsdetails["companyname"] - Client Info Company Name
- $clientsdetails["fieldname"] - etc...
- $clientsdetails["customfields1"] - Client Info Custom Field #1
- $subtotal
- $tax
- $taxrate
- $credit
- $total
- $status - Paid, Unpaid or Cancelled
- $paymentmethod
- $notes
- $companyname - Your Company Name
- $companyurl - Your Default Website URL
- $companyaddress - Your Company Address
- $currencysymbol - Active Currency Symbol
- $invoiceitems - Array of invoice items
